A driving motor for a vehicle uses a resolver to detect a velocity of the driving motor and an angle of a rotor. A signal detected by the resolver is transmitted to a microcomputer via a resolver to digital converter. The microcomputer is configured to determine a failure of a signal line of the resolver via the signal, which is transmitted via the resolver to digital converter. In other words, a system configured to determine a failure in a resolver according to a related art recognizes when the system receives a sin/cos monitored signal (sin/cos signal) and the received sin or cos signal maintains about 0V or about 5V for at least a predetermined time as a disconnection failure of a sin or cos signal line.
The system configured to determine a failure in a resolver according to a related art needs the driving motor to set a time that determines the failure to be sufficiently long in the vicinity of (e.g., near) the corresponding angle, or may be implemented to operate only at a predetermined velocity or greater. Moreover, when the time that senses the failure is set to greater than a particular time, even though a real failure occurs within the resolver, an additional failure (e.g., an overcurrent failure, or the like) may cause a power module failure and a vehicle driving error since a current control for the driving motor is performed using a wrong angle of a rotor of the motor until the failure is determined.
In addition, the system for determining a failure within a resolver according to the related art may not determine the failure in the signal line of the resolver in a low velocity driving section of the driving motor since the system that determines a failure within a resolver according to the related art may determine the failure in the signal line of the resolver when the driving motor operates at the predetermined velocity or greater.